Deflectable guide

ABSTRACT

Described herein are devices and methods for guide catheters having one or more regions of increased flexibility. A flexibility region comprises one tubular segment of the guide catheter with a non-linear longitudinal seam between two non-concentric layers of material having different durometers. A non-linear seam, such as a zig-zag or sinusoidal configuration, permits controlled compression of lower durometer material between portions of higher durometer material.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. §119(e) to U.S.Provisional Application No. 61/051,292, filed on May 7, 2008, and toProvisional Application No. 61/160,670 filed on Mar. 16, 2009, which arehereby incorporated by reference in their entirety.

BACKGROUND

Guide catheters are used in a variety of therapeutic and diagnosticmedical procedures to facilitate insertion of instruments andimplantable components. Guide catheters often comprise a rigid materialor support structure to provide the torqueability and pushabilitycharacteristics that facilitate passage of the guide catheter to aparticular site. With the stiffer material or support structure, theresponsiveness of the distal portion of the guide catheter tomanipulation of the proximal portion of the guide catheter typicallyimproves. A flexible material, however, permits the guide catheter tonavigate around tight bends and other hard-to-reach places. Althoughsome guide catheters may be generically configured for use with avariety of procedures, some guide catheters have a particular length,stiffness and distal tip shape adapted for access to a specific tissueor organ.

BRIEF SUMMARY

Described herein are devices and methods for guide catheters having oneor more deformation zones. In one embodiment, a deformation zonecomprises a tubular segment of the guide catheter with a longitudinalinterface between two non-concentric sections of material havingdifferent durometers. The longitudinal interface may be linear ornon-linear. A non-linear interface between the two sections of material,such as a zig-zag or sinusoidal interface, may permit controlleddeformation of the lower durometer material between portions of higherdurometer material. This deformation may include stretching and/orcompression. In some embodiments, the deformation zone reduces thebuckling of higher durometer material that may interfere with insertionor withdrawal of catheters or instruments from the lumen of the guidecatheter.

In some embodiments, the guide catheter may further comprise a pull wireor ribbon which is secured to the guide catheter distal to thedeformation zone and is slidable along a pull wire lumen through aproximal actuator. The pull wire may be used to control deflection ofthe guide catheter at the deformation zone. The actuator may be, forexample, a rotatable knob, a pivoting lever or a slider. The actuatormay comprise a bias element, such as a spring or other elastic element,that may be used to bias the pull wire toward a particular position. Theactuator may also comprise a locking mechanism that may be used tomaintain the pull wire in one or more positions.

In some embodiments, a catheter is provided, comprising a deformationzone comprising a proximal end, a distal end, a longitudinal length anda longitudinal axis therebetween, a lower durometer segment, a higherdurometer segment, and a first longitudinal interface between the lowerdurometer segment and the higher durometer segment, wherein the firstinterface has a length greater than the longitudinal length of thedeformation zone. The lower durometer segment and/or the higherdurometer segment may comprise a polymeric material. The first interfacemay have a non-linear configuration, including but not limited to azig-zag configuration, or intercalating portions of the lower durometersegment and the higher durometer segment. In some embodiments, thedeformation zone may further comprise a second interface between thelower durometer segment and the higher durometer segment, wherein thesecond interface is separate from the first interface. In oneembodiment, the second interface may have a length greater than thelongitudinal length of the deformation zone. In another embodiment, thedeformation zone may have a first configuration and a secondconfiguration, wherein the second configuration has an increased bendcompared to the first configuration. The second configuration may be acurved configuration having a lesser curvature and a greater curvature,and wherein the lower durometer segment is located along the lessercurvature. In some further embodiments, the catheter may furthercomprise a means for controlling bending of the deformation zone. Insome instances, the higher durometer segment has an angular width of atleast about 45 degrees on an axial cross-section of the deformationzone. In other embodiments, the lower durometer segment has an angularwidth of at least about 90 degrees or at least about 180 degrees on theaxial cross-section of the deformation zone.

In another embodiment, a catheter is provided, comprising a deformationzone comprising a proximal end, a distal end, a longitudinal lengththerebetween, a first polymeric layer comprising a proximal edge, adistal edge, a first lateral edge and a second lateral edge, and asecond polymeric layer comprising a proximal edge, a distal edge, afirst lateral edge and a second lateral edge, wherein the firstpolymeric material has a lower durometer than the second polymericmaterial, and wherein the first lateral edge of the first polymericlayer is joined to at least a portion of the second lateral edge of thesecond polymeric layer, and wherein the second lateral edge of the firstpolymeric layer is joined to at least a portion of the first lateraledge of the second polymeric layer.

In another embodiment, a method for treating a patient is provided,comprising providing a catheter having a lower durometer regioncomprising at least one compressible portion and a greater durometerregion comprising at least two constricting portions in an alternatingconfiguration with the last least one compressible portion, bending thecatheter such that the at least two constricting portions of the higherdurometer region compresses the at least one compressible portion of thelower durometer region, and passing a tubular body down a passageway ofthe catheter.

In still another embodiment, a system for treating a patient isprovided, comprising a guide catheter comprising a longitudinal axis, aguide lumen, and at least one deformation zone, the at least onedeformation zone comprising two segments of polymeric material ofdifferent durometers and a longitudinal interface therebetween withrespect to the longitudinal axis of the guide catheter, a tunnelcatheter comprising a tubular body with a tunnel lumen, wherein thetubular body is configured for insertion into the guide lumen of theguide catheter, and a delivery catheter comprising an anchor retainingcavity and an anchor delivery mechanism, wherein the delivery catheteris configured for insertion into the tunnel lumen of the tunnelcatheter. The tubular body of the tunnel catheter may further comprise aplurality of delivery apertures in communication with the tunnel lumen.In some embodiments, the longitudinal configuration between the twosegments of polymeric material comprises a reciprocating longitudinalconfiguration.

In one embodiment, a method for accessing a cardiac region of a patientis provided, comprising providing a steerable guide catheter comprisingtwo polymeric materials forming a longitudinal interface therebetween,where the two polymeric materials comprise a first polymeric materialhaving a first durometer and a second polymeric material having seconddurometer greater than the first durometer, passing the steerable guidecatheter through a cardiac valve orifice, compressing the firstpolymeric material with the second polymeric material about thelongitudinal interface, and steering the steerable guide catheter into asubvalvular region adjacent the cardiac valve orifice.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and method of using the invention will be betterunderstood with the following detailed description, along with theaccompanying illustrations, in which:

FIG. 1 is a cross-sectional view of a catheter body with a pull wire;

FIGS. 2A and 2B are schematic side elevation and cross sectional viewsof the catheter body of FIG. 1 in a bent configuration, respectively;

FIG. 3A illustrates one embodiment of a deflectable guide catheter; FIG.3B is a detailed view of the catheter body of the deflectable guidecatheter in FIG. 3A; FIG. 3C is a detailed view of the distal end of thedeflectable guide catheter in FIGS. 3A and 3B; FIGS. 3D and 3E arevarious cross sectional views of the catheter body of FIG. 3B;

FIGS. 4A to 4C are schematic representations of a deformation zone invarious configurations;

FIG. 5 represents one embodiment of the interface between two sectionsof catheter body material;

FIGS. 6A to 6D represent other embodiments of the interface between twosections of catheter body material;

FIGS. 7A to 7C represent various embodiments of the interface betweentwo sections of catheter body material;

FIG. 8A illustrates one embodiment of a deformable zone of a deflectableguide catheter; FIGS. 8B and 8C represent various cross sections of thedeformable zone depicted in FIG. 8A;

FIG. 9A illustrates another embodiment of a deformable zone of adeflectable guide catheter; FIGS. 9B and 9C represent various crosssections of the deformable zone depicted in FIG. 9A;

FIG. 10A illustrates another embodiment of a deformable zone of adeflectable guide catheter; FIG. 10B represents a cross section of thedeformable zone depicted in FIG. 10A;

FIG. 11A is a schematic representation of one embodiment of a steeringmechanism; FIG. 11B is a schematic representation of another embodimentof a steering mechanism;

FIGS. 12A and 12B depict one embodiment of a deflectable guide catheterused to reach the subvalvular groove region of a mitral valve; and

FIGS. 13A to 13E are schematic representations of a deflectable guidecatheter used to implant a cinchable implant along the subvalvularregion of a mitral valve.

FIG. 14A is a superior elevational view of a variation of a steerableguide catheter; FIG. 14B is a detailed superior elevational view of thedistal end of the guide catheter; FIG. 14C is a side elevational view ofthe distal end of the guide catheter; FIG. 14D is a detailed superiorelevational view of the proximal end of the guide catheter; and FIG. 14Eis a longitudinal cross sectional view of the steering mechanism of theguide catheter.

FIG. 15A is a perspective view of a variation of a hemostatic seal; FIG.15B is a posterior elevational view of the seal; and FIG. 15C is across-sectional view of the seal.

FIG. 16 is a posterior elevational view of another variation of ahemostatic seal.

DETAILED DESCRIPTION OF THE INVENTION

The ease of inserting a catheter to a body location may be influenced bya number of catheter characteristics. While a catheter made from stiffermaterials may improve its user responsiveness relating torqueability andpushability over longer insertion distances, stiffer catheter materialsmay affect the catheter's maneuverability through tight anatomicalbends. In some cases, catheter maneuverability may be improved by usinga steering mechanism to position the catheter tip in the desiredorientation or direction. FIG. 1 illustrates one example of a steerablecatheter segment, comprising a tubular catheter body 4 with one or moreconduits 6 and a pull lumen 8 containing a pull member 10. Typically,pull member 10 is attached distally to catheter body 4 such that, whenpulled proximally, pull member 10 will cause catheter body 4 to bend, asshown in FIG. 2A. While a steering mechanism 12 may improve the bendingrange of stiffer catheter materials, such materials may cause creases 14or other discontinuities in catheter body 4 when bent, as illustrated inFIG. 2A. Further, such creases 14 may impair the ability to passinstruments 16 or components down conduit 6, as shown in thecross-sectional view of FIG. 2B.

In one embodiment, shown in FIG. 3A, a steerable catheter 2 with one ormore deformation zones 18 is provided. Referring to FIG. 3C, deformationzone 18 may comprise a segment of catheter body 4 comprising a firstlayer segment 20 and a second layer segment 22 arranged with alongitudinal interface 24 therebetween. First layer segment 20 andsecond layer segment 22 comprise different physical characteristics suchthat first layer segment 20 is able to compress or stretch when flexed.In some embodiments, first layer segment 20 comprises a material havinga lower durometer than second layer segment 22. In embodiments wheredeformation zone 18 is formed by two layer segments, two longitudinalinterfaces are formed where the two lateral borders of each layersegment form a longitudinal interface with the complementary lateralborder of the other layer segment. In other embodiments, first layersegment 20 may comprise a structural geometry, such as surface cuts orgrooves, that may help control or distribute flexion forces to reduceimpingement of any conduits.

In some embodiments, longitudinal interface 24 generally has a linear orsimple curve configuration similar to the longitudinal axis of catheterbody 4. In the embodiment depicted in FIG. 3C, however, longitudinalinterface 24 is oriented with a similar axis as the longitudinal axis ofcatheter body 4 but with a zig-zag configuration. Referring to FIG. 4A,the zig-zag configuration of longitudinal interface 24 comprisesalternating protruding sections of first layer segment 20 and secondlayer segment 22. These alternating protruding sections, shown in thisparticular embodiment as triangular sections 26 and 28, have sidelengths 30 and 32 which meet to form an angle 34 between two adjacentsides 30. In FIG. 4C, when deformation zone 18 is straightened from itsconfiguration in FIG. 4B, triangular sections 26 of first layer segment20 are stretched or relieved of compression as angle 34 is increased bythe angular separation of triangular sections 28 of second layer segment22. In contrast, as depicted in FIG. 4A, when deformation zone 18 isacutely bent relative to FIG. 4A, triangular sections 26 of first layersegment 20 are compressed as angle 34 is decreased by the angularreduction of triangular sections 28 of second layer segment 22. In someembodiments of the invention, the zig-zag pattern may reduce theincidence or degree of pinching or creasing of any conduits in catheterbody 4 by controlling compression of the lower durometer material infirst layer segment 20 with the protruding sections 28 of the higherdurometer material in second layer segment 22. Further, in someembodiments, the zig-zag pattern may provide a more even distribution ofthe forces along the full length of deformation zone 20, compared tosimple linear or simple curved interfaces. In some embodiments, secondlayer segment 22 may be contiguous with tubular body 36.

In one embodiment, deformation zone 18 is configured to bend from about180 degrees to about 30 degrees, about 180 degrees to about 45 degreesin some embodiments, and about 180 degrees to about 90 degrees in otherembodiments. In some embodiments, deformation zone 18 is able to bend intwo or more directions and/or two or more planes from its straight orbase configurations. The range of bending in two or more directions orplanes need not be symmetrical with respect to the straight or baseconfigurations. The base configuration need not be linear. Variousembodiments of non-linear base configurations are discussed later.

In some embodiments, catheter body 4 may have a total length of about 20cm to about 200 cm or more, about 60 cm to about 160 cm in otherembodiments, and about 100 cm to about 120 cm in still otherembodiments. In one embodiment, catheter body 4 may have an outerdiameter of about 5 F to about 34 F, in other embodiments about 8 F toabout 20 F, and about 12 F to about 16 F in some embodiments. In someembodiments of the invention, conduit 6 is sized to accept catheters orinstruments with a size of about 3 F to about 30 F, in a few embodimentsabout 6 F to about 16 F, and about 8 F to about 12 F in otherembodiments.

Catheter body 4 can be formed from any of a variety of materials.Examples of suitable materials include but are not limited to polymers,such as polyether-block co-polyamide polymers, copolyester elastomers,thermoset polymers, polyolefins (e.g., polypropylene or polyethylene,including high-density polyethylene and low-density polyethylene),polytetrafluoroethylene, ethylene vinyl acetate, polyamides, polyimides,polyurethanes, polyvinyl chloride (PVC, fluoropolymers (e.g.,fluorinated ethylene propylene, perfluoroalkoxy (PFA) polymer,polyvinylidenefluoride, etc.), polyetheretherketones (PEEKs),Polyetherketoneketones (PEKKs) and silicones. Examples of polyamidesthat may be included in tunnel catheter (410) include Nylon 6 (e.g.,Zytel® HTN high performance polyamides from DuPont™ ), Nylon 11 (e.g.,Rilsan® B polyamides from Arkema Inc.), and Nylon 12 (e.g., Giilamid®polyamides from EMS-Grivory, Rilsan® A polyamides from Arkema Inc., andVestamid® polyamides from Degussa Corp.). In one embodiment, catheterbody 4 comprises PEBAX®, a polyether block amide (PEBA) available fromATOMCHEM POLYMERS of Birdsboro, Pa. First layer segment 20 and secondlayer segment 22 may comprise different materials or the same generaltype of material but with different durometers. In some embodiments, thedurometer of the material may range from about 5 D to about 72 D,sometimes about 35 D to about 72 D, other times about 35 D to about 55D, or about 55 D to about 72 D. Catheter body 4 may comprise one or morelayers, and sometimes two or more layers. Although FIGS. 3A to 3C depictfirst layer segment 20 and second layer segment 22 as forming theoutermost layer of deformation zone 18, in other embodiments of theinvention, these layer segments 20 and 22 may be covered by one or moreother layers or reinforcing structures. Catheter body 4 need notcomprise the same number of polymeric layer along its entire length.

Catheter body 4 and/or conduit 6 may be reinforced (e.g., with tubularor arcuate braiding, circular loops, helical structures, or longitudinalsupports). The reinforcing structure or structures may comprise ametallic material or a non-metallic material. Metallic materials thatmay be used include but are not limited to stainless steel such as 316L,nitinol and cobalt-chromium.

Referring back to the specific embodiment depicted in FIGS. 3A and 3B,catheter body 4 may comprise a proximal section 44 and a distal section46. Referring to FIG. 3D, in this specific embodiment, proximal section44 comprises a tubular body 36 and a single conduit 6 optionally linedwith a coating 38. Typically, proximal section 44 has a linearconfiguration, but in other embodiments, proximal section 44 may have anon-linear configuration, including angled and curved configurations orcombinations thereof. In some embodiments, tubular body 36 optionallycomprises one or more reinforcement structures 40. In some embodiments,tubular body 36 may comprise PEBAX 72 D, coating 38 may comprise PTFEand reinforcement structure 40 may comprise a tubular stainless steelwire braid surrounding conduit 6. Proximal section 44 further comprisesa pull lumen 8 and pull member 10 within the wall of proximal section44. Pull lumen 8 and/or pull member 10 may also be coated with alubricious coating such as PTFE. In further embodiments, pull lumen 8may be reinforced with a material such as polyimide. As shown in FIG.4D, in some embodiments of the invention, the wall thickness of catheterbody 4 or proximal section 36 may vary along their longitudinal lengthsor circumferences.

In some embodiments, distal section 46 may comprise a particular shapewith optional multiple sections. For example, as shown in FIG. 3C,distal section 46 may comprise a pre-deformation section 48, a secondsection comprising deformation zone 18, a post-deformation section 50and a distal tip 52. In this particular embodiment, pre-deformationsection 48 comprises a curved configuration but otherwise may havesimilar components as proximal section 44, with a tubular body 36,conduit 6, and pull member 10 within pull lumen 8. In other embodimentsof the invention, the components and features of pre-deformation section48 may be different from proximal section 44. In this particularembodiment, distal to pre-deformation section 48 is deformation zone 18configured with a curved configuration with a curvature opposite ofpre-deformation section 48. In other embodiments of the invention,deformation zone 18 may have a linear or angled configuration, with anangular orientation from about 0 degrees to about 359 degrees withrespect to pre-deformation section 48. In some embodiments, deformationzone 18 may have an angular orientation of about 0 degrees, about 15°,about 30°, about 45°, about 60°, about 75°, about 90°, about 105°, about120°, about 135°, about 150°, about 165°, about 180°, about 195°, about210°, about 225°, about 240°, about 255°, about 270°, about 285°, about300°, about 315°, about 330°, or about 345°. The bending plane ofdeformation zone 18, however, need not be the same plane as its curvedconfiguration and may have an angular orientation from about 0 degreesto about 359 degrees to the plane of its curved configuration. In someembodiments, the bending plane of deformation zone has an angularorientation of about In some embodiments, deformation zone 18 may havean angular orientation of about 0 degrees, about 15°, about 30°, about45°, about 60°, about 75°, about 90°, about 105°, about 120°, about135°, about 150°, about 165°, about 180°, about 195°, about 210°, about225°, about 240°, about 255°, about 270°, about 285°, about 300°, about315°, about 330°, or about 345° with respect to the plane of its curvedconfiguration.

In some embodiments, deformation zone 18 may have a longitudinal lengthof about 0.75 inches to about 10 inches, some embodiments about 1 inchto about 4 inches or more, and in other embodiments about 1.5 inches toabout 2 inches in length. In some embodiments of the invention,deformation zone 18 may have similar inner and outer diameters asdescribed for catheter body 4, but in other embodiments, deformationzone 18, the inner diameter of conduit 6 may be smaller or larger andthe outer diameter of tubular body 36 may be smaller or larger.

Referring to FIG. 3E, in this specific embodiment, deformation zone 18comprises an outer layer 42 formed by first layer segment 20 and secondlayer segment 22. Conduit 6, pull lumen 8, pull member 10 andreinforcement structure 40 are arranged in deformation zone 18 similarto proximal section 44, except that a second reinforcement structure 54is provided. In this embodiment, second reinforcement structure 54comprises a second tubular stainless steel braid surrounding conduit 6and pull lumen 8. In some embodiments, second reinforcement structure 54may originate proximally in pre-deformation section 48 of distal section46. The portion 56 of tubular body 36 between reinforcement structures40 and 54 may comprise a similar material as segments 20 or 22, or adifferent material.

Although several embodiments depicted and described herein have a singleconduit 6, in other embodiments, two or more conduits may be provided.Embodiments of the invention with multiple conduits need not haveconduits with the same diameter, shape or cross-sectional area.Furthermore, any one conduit need not have the same diameter, shape orcross-sectional area along its entire length. Thus, some conduits maycomprise a circular shape, but in other embodiments the conduits may beoval, square, rectangular or any other shape. As mentioned previously,in some embodiments of the invention, conduit 6 may comprise alubricious coating, including but not limited to PTFE.

In some embodiments, catheter body 4 may also comprise one or moreradio-opaque structures or materials to facilitate identification andlocalization of guide catheter 2 with radiographic imaging. The imagingmay include but is not limited to fluoroscopy, CT imaging, MRI imaging,and intravascular ultrasound or echocardiography. The radio-opaquestructures may be found along the entire length or a portion of thelength of catheter body 4. In some embodiments, at least oneradio-opaque structure is located at post-deformation section 50 ordistal tip 60.

As mentioned previously, segments 20 and 22 may be joined at theirlateral edges to form two longitudinal interfaces 24. In this specificembodiment, segment 20 comprises PEBAX 35 D while segment 22 comprisesPEBAX 72 D. Because segments 20 and 22 in this specific embodiment havegenerally semi-circular configurations, longitudinal interfaces 24 havegenerally 180 degree opposite locations with respect to conduit 6. Inother embodiments, however, deformation zone 18, interfaces 24 may beangularly closer together, or may comprise three or more interfaces 24.

Referring back to FIG. 3C, in some embodiments, distal section 46further comprises a post-deformation section 50 distal to deformationzone 18. Post-deformation section 50 may be straight, angled or curved,or a combination thereof. Post-deformation section 50 may have alongitudinal length of about 0.25 inches to about 5 inches or more,sometimes about 0.5 inches to about 2 inches, and occasionally about0.75 inches to about 1.25 inches. Post-deformation section 50 maycomprise one or more layers. In some embodiments, post-deformationsection 50 comprises the same material as one of the segments fromdeformation zone 18, but in other embodiments, post-deformation section50 may comprise a material having a higher, lower or intermediatedurometer. For example, in one embodiment of the invention, segments 20and 22 of deformation zone 18 comprise PEBAX 35 D and 72 D,respectively, while post-deformation section 50 comprises PEBAX 55 D.Post-deformation section 50 may or may not include one or morereinforcement structures. In some embodiments, the reinforcementstructure may be contiguous with reinforcement structures 40 and/or 54,and in some embodiments may include a reinforcement structure differentfrom reinforcement structures 40 and/or 54.

In some embodiments, one or more conduits from the proximal portions ofcatheter body 4 may pass through post-deformation section 50 orterminate within it. In embodiments of the invention with a singledeformation zone and/or steering mechanism, however, pull lumen 8 and/orpull member 10 may terminate within post-deformation section 50. Tofacilitate the exertion of force in distal section 46 of catheter body4, pull member 10 may comprise a distal pull structure 58. Pull member10 may be coupled to distal pull structure 58 or be contiguous withdistal pull structure 58. In the embodiment illustrated in FIG. 3C,distal pull structure 58 may comprise a ring-like structure embedded inpost-deformation section 50. In alternate embodiments, distal pullstructure 58 may comprise a helical winding of pull member 10 or someother wire-based configuration. Pull member 10 may comprise any of avariety of materials and structures sufficient to transmit longitudinalforces along a length of catheter body 4. Pull member 10 and distal pullstructure 58 may be metallic, non-metallic or a combination thereof,including but not limited to stainless steel, nitinol, nylon or otherpolymeric material. In some embodiments, pull member 10 may be coated,for example, to facilitate sliding in pull lumen 8. Such coatings mayinclude PTFE.

In some embodiments, pull member 10 may comprise a structure and amaterial whereby pull member 10 can exert force on catheter body 4 onlywhen pulled. In these embodiments, catheter body 4 may have apreconfigured shape such that when the force acting on pull member 10 isreleased, catheter body 4 is biased to return to its preconfiguredshape. In other embodiments, pull member 10 has a sufficient stiffnesssuch that pull member 10 may also be pushed to facilitate bending ofcatheter body 4 in a direction generally different or opposite from thebending that occurs when pull member 10 is pulled. In other embodimentsof the invention, distal pull structure 58 may be located withindeformation zone 18.

As depicted in FIG. 3C, catheter body 4 may optionally comprise a distaltip 60 with a different structure or configuration relative topost-deformation section 50. In embodiments, distal tip 60 is configuredas an atraumatic tip and may comprise a material and/or structuredifferent from tubular body 36, deformation zone 18 or post-deformationsection 50. In some embodiments, distal tip 60 comprises a material witha durometer equal to or lower than a material found in eitherdeformation zone 18 or post-deformation section 50. In one specificexample, distal tip 60 comprises PEBAX 35 D, while post-deformationsection 50 comprises PEBAX 55 D, segment 20 comprises PEBAX 35 D,segment 22 comprises PEBAX 72 D and tubular body 36 comprises PEBAX 72D. Distal tip 60 may have a longitudinal length of about 1 mm to about20 mm or more, sometimes about 2 mm to about 10 mm, and occasionallyabout 5 mm. The inner and outer diameters of distal tip 60 may be thesame or different from other portions of catheter body 4.

In some embodiments, interface 24 may have a relatively linearconfiguration 65, as depicted in FIG. 5, or a non-linear configurationother than a zig-zag pattern. For example, interface 24 may comprise areciprocating pattern including but not limited to a square wave pattern66, a scalloped pattern 68, and a sinusoidal pattern 70 as depicted inFIGS. 6A to 6C, respectively. As shown in FIG. 6D, the reciprocatingpattern 72 need not have symmetric subsegments. In this embodiment forexample, the leading edge 74 has a different length and angle as thetrailing edge 76.

As depicted in FIGS. 7A to 7C, interface 24 need not comprise the samerepeating pattern along its entire length. For example, in theembodiment depicted in FIG. 7A, interface 24 comprises a linear portion78 followed by a zig-zag portion 80 and another linear portion 82. Inanother embodiment depicted in FIG. 7B, interface 24 comprises the samepattern but with sections of low and high amplitude 84 and 86,respectively. In still another embodiment shown in FIG. 7C, interface 24comprises a pattern of similar amplitude but contains portions withrelatively shorter and longer repeating lengths 88 and 90, respectively.These features may be mixed and matched to achieve the desiredstructural features in deformation zone 18.

As mentioned previously, the embodiment depicted in FIGS. 3A to 3Ecomprises a deformation zone 18 with two similarly sized semi-circularsegments 20 and 22, and two interfaces 24 about 180 degrees apart withrespect to conduit 6. In other embodiments, however, segments 20 and 22may have different sizes and shapes. In FIG. 8A, for example, segment 20has a reduced width at one or more ends, resulting in interfaces 24forming a narrower angle in one section (FIG. 8B) as compared to anothersection (FIG. 8C). In other embodiments of the invention, as depicted inFIG. 9A, the deformation zone may comprise a third layer segment 92,resulting in additional interfaces 94, 96.

In some embodiments, such as the embodiment depicted in FIGS. 3A to 3E,deformation zone 18 comprises a single steering mechanism 12, but inother embodiments, multiple pull lumens with multiple pull members maybe provided. In FIG. 10A, for example, the deformation zone comprisesthree layer segments 20, 22 and 92 arranged to facilitate the bending ofthe deformation zone in opposite directions. As shown in FIG. 10B, twosteering mechanisms 12 and 98 may be provided to facilitate bending inopposite directions. In other embodiments, the two or more steeringmechanisms may be located about 15°, about 30°, about 45°, about 60°,about 75°, about 90°, about 105°, about 120°, about 135°, about 150°,about 165°, about 180°, about 195°, about 210°, about 225°, about 240°,about 255°, about 270°, about 285°, about 300°, about 315°, about 330°,or about 345° with respect to the plane of its curved configuration. Inother embodiments of the invention, multiple steering mechanisms withdifferent distal longitudinal terminations along the length of catheterbody 4 may be provided, to facilitate along different lengths ofbending. The longitudinal separation may be about 1 cm to about 50 cm ormore, sometimes about 5 cm to about 20 cm, and at other times about 5 cmto about 10 cm apart.

Any of a variety of control mechanisms may be used to manipulate one ormore pull members 10. In FIG. 3A, for example, a rotatable knob 100 maybe provided on steering catheter 2. Referring to FIG. 11A, the proximalend 102 of pull member 10 may be attached to a rotating knob 102, oralternatively to a pivoting lever 104, as illustrated schematically inFIG. 11B. In other embodiments, pull member 10 may be manipulated by apull ring or a slider. Steering mechanism 12 may further comprise a biasmember (not shown), such as a spring or elastic member, to bias distalsection 46 to a particular position. Steering mechanism may alsocomprise a releasable locking mechanism to maintain pull member 10 in adesired position.

In some embodiments, the knob 100 or other proximal control member iscoupled to a single pull member. In other embodiments with multiple pullmembers, one or more control members may be provided, particularly inembodiments with multiple deformation zones, but the number of controlmembers need not be equal to the number of pull members. In theseembodiments, two or more pull members may be coupled to a single controlmember. For example, a knob or slider may be engaged to dual pullmembers with a neutral position having a relative equal or zero forceacting between the two pull members. Manipulation of the knob or slidein one direction away from the neutral position will exert force on onepull member, while manipulation of the slide or knob in the otherdirection away from the neutral position will exert force on the otherpull member. The configuration of catheter body 4 associated with theneutral position may be a linear or a non-linear configuration.

Referring back to FIG. 3A, the proximal end of guide catheter 2 may haveone or more ports 106, 108 and 110. These ports may communicate withconduit 6 or other conduits of multi-conduit embodiments of theinvention. In some embodiments, one or more ports may be provided toobtain blood samples, for injection of intravenous fluids, radiographicor therapeutic agents, or for the attachment of a pressure transducer.One or more ports 106, 108 and 110 may be configured with a hemostasisvalve to reduce fluid or blood leakage, and/or a lock for resistingdisplacement of any components inserted into that port. In oneembodiment, the lock is a releasable lock that can be released andre-engaged as needed. In some embodiments, the components used with aport may include one or more indicia along its length that may be usedto identify the degree of insertion into guide catheter 2.

In the specific embodiment depicted in FIG. 3A, port 106 associated withconduit 6, may be configured for the insertion of a tunnel catheter orother instrument. In some embodiments, a tunnel catheter may be used inconjunction with guide catheter 2 to provide additional guidance beyondthe distal end of guide catheter 2. Providing a guidance pathway usingboth guide catheter 2 and a tunnel catheter may be easier to position ata target site or be easier to manufacture than a single guide catheterconfigured to traverse the entire guidance pathway.

For example, FIG. 12A depicts one exemplary use of a guide catheter 112with a deformation zone 114. Guide catheter 112 may be inserted from aperipheral vascular site and passed in a retrograde direction throughthe aorta A. As guide catheter 112 passes through the aortic valve, thesteering mechanism of guide catheter 112 may be manipulated to bendtoward the subvalvular region 116 adjacent the mitral valve leafletsMVL, as shown in FIG. 12B. Although a sharp turn may be formed in guidecatheter 112 by providing a pathway from the aortic valve to thesubvalvular region, instead of looping guide catheter 112 below thechordae tendinae or the apex of the left ventricle, deformation zone 18permits controlled flexion that does not impinge or infold into theconduit provided in guide catheter.

In another variation, shown in FIGS. 14A, the steerable catheter 4000comprises a deformation region 4002 with a segment of the catheter body4004 having a first layer segment 4006 and a second layer segment 4008with a generally linear longitudinal interface 4010 therebetween. Thefirst layer segment 4006 comprises a lower durometer material and thesecond layer segment 4008 comprises a higher durometer material. Thecatheter body 4004 may further comprise a proximal shaft 4012 and adistal shaft 4014 with respect to the deformation region 4002. Theproximal shaft 4012 may comprise a tubular configuration with at leastone inner lumen (not shown) that may be optionally lined with a coating.The proximal shaft 4012 may have a generally linear configuration, butin other variations, proximal shaft 4012 may have a non-linearconfiguration, including angled and curved sections or combinationsthereof, such as the arch curve region 4018. The distal shaft 4014 mayalso have a linear or curved configuration, such as the valve curveregion 4020 depicted in FIGS. 14B and 14C. Additional variations andmethods of use for these and other deflectable guide catheters aredescribed in U.S. Provisional Application No. 61/160,670 entitled“VISUALIZATION METHODS AND RELATED DEVICES AND KITS”, filed Mar. 16,2009, which is hereby incorporated by reference in its entirety. In somevariations, the proximal shaft 4012 may comprise one or morereinforcement structures 4022, such as tubular or arcuate braiding orinterweaving, circular loops, helical structures, or longitudinalsupports). The reinforcement structure may comprise one or more metallicor non-metallic materials as described previously. In one example, theproximal shaft 4012 may comprise an outer layer of PEBAX 72 D, and thereinforcement structure 4022 may comprise a tubular stainless steel wirebraid, which in turn may have an inner coating of PTFE. In the exampleof FIG. 14A, the distal shaft 4014 comprises a material having adurometer between the durometer of the first and second segments 4006and 4008, but in other examples, the durometer may be generally equalto, less than or greater than the first and second segments 4006 and4008, respectively. The distal shaft 4014 may also comprise anatraumatic tip 4024, which may comprise a material having lowerdurometer than the rest of the distal shaft 4014, or may be tapered orotherwise shaped to be more flexible or deformable. The distal shaft4014 may comprise a linear or non-linear configuration, and may beoriented in the same or a different plane with respect to thedeformation region 4002 and/or proximal shaft 4012, as shown in FIG.14D.

Referring to FIG. 14B, the proximal shaft 4012 may further comprise apull lumen 4026 and a pull member 4028 within the wall of proximal shaft4012. The pull lumen 4026 and/or pull member 4028 may also be coatedwith a reduced friction coating, such as PTFE. In further variations,the pull lumen 4026 may be reinforced with a material such as polyimide.The pull member 4028 may comprise any of a variety of materials,including but not limited to stainless steel, nylon, polyimide, and thelike. The pull lumen 4026 and/or pull member 4028 may terminate withinthe deformation region 4002 or the distal shaft 4014. To facilitate theexertion of force in the distal shaft 4014 of the catheter body 4004,the pull member 4028 may comprise a distal pull structure 4030, such asa ring-like structure embedded in the distal shaft 4014. As notedelsewhere, the pull member 4028 may comprise any of a variety ofmaterials and structures sufficient to transmit longitudinal forcesalong a length of the catheter body 4004. The pull member 4028 and thedistal pull structure 4030 may be metallic, non-metallic or acombination thereof, including but not limited to stainless steel,Nitinol, nylon or other polymeric material. In some variations, the pullmember 4028 may be coated, for example, to facilitate sliding in thepull lumen 4026, such as PTFE.

FIG. 14D depicts the proximal end 4030 of the steerable catheter 4000,comprising a rotatable knob 4032, a guide hub interface 4034, ahemostasis valve 4036 and a stopcock 4038. The knob 4032 may beconfigured to adjust the tension of the pull member 4028 by knobrotation, but in other variations, tension adjustment may occur bypulling the knob. Referring to FIG. 15E, the pull member 4028 may beattached to a hypotube 4040 by crimping, welding, adhesives or the like.The hypotube 4040 may be attached to a key structure 4042 which forms acomplementary interfit with the knob 4032 to axially displace the pullmember 4028 while permitting relative rotational movement between theknob 4032 and the key structure 4042. The key structure 4042 may also beaxially secured to the knob 4032 using a screw 4044 or other attachmentstructure which permits relative rotational movement. In othervariations, the knob may be configured to transmit rotational movementto the pull member.

An inner sleeve 4046 with an outer threaded surface 4048 may be attachedto the base 4050 of the steering assembly. The outer threaded surface4048 may interface with the inner threaded surface 4052 of the knob4032. In some variations, to permit axial movement while restrictrotational movement of the pull member 4028, the hypotube 4040 or thekey structure 4042 may be configured with a non-circular shape and/orone or more side protrusions which may resist rotational movement alongan inner lumen 4054 of the inner sleeve 4046. For example, FIG. 14Edepicts the inner lumen 4054 comprising an elongate groove 5056 whichaccommodates axial movement of the set screws 5058 attached to andprotruding from the key structure 4042 while restricting rotationaldisplacement of the screws 5058.

To reduce the risk of blood or fluid leakage from the catheter 4000during a procedure, the proximal end 4030 may further comprise ahemostasis valve or seal 5060 through which instruments may be insertedor withdrawn. The hemostatic seal may comprise any of a variety ofconfigurations known in the art. In some examples, the hemostatic sealmay comprise one or more slits on a septum or sealing member which formsone or more seal flaps. Upon insertion of an instrument or devicethrough the sealing member, the seal flaps deform or deflect to permitpassage of the device while exerting force around a perimeter of thedevice to substantially resist passage of fluid or gas through thesealing member. Referring to FIGS. 15A to 15C, in some examples, thesealing member 4100 has a seal opening 4102 comprising at least onenon-linear slit 4104 a-d with respect to the seal face 4106 or atransverse plane of the seal axis 4108. In the depicted example, thesealing opening 4102 comprises four arcuate or spiral-shaped slits 4104a-d arranged about the seal axis 4108. Each of the slits 4104 a-d hasthe same relative shape and size as the other slits 4104 a-d anduniformly spaced around the axis 4108, but in other examples, adifferent number of slits may be provided, one or more slits may have adifferent size or shape, the slits may be non-uniformly spaced ornon-symmetrically arranged, and/or may intersect at location differentfrom the center of the seal face 4106. In FIG. 16, for example, thesealing member 4130 comprises a plurality of multi-angled slits 4132a-d. Referring back to FIG. 14D, the hemostasis valve 4036 and thestopcock 4038 may be detached from the guide hub 4034 to permit directinsertion of instruments into the catheter 4000, or to attach otherconfigurations of hemostasis seals, valves, connectors, sensors and thelike.

Referring back to FIGS. 15A to 15C, the slits 4104 a-d may have agenerally orthogonal orientation through the seal face 4106, or may beangled or skewed. In some examples, the slits 4104 a-d may be generallyangled with respect to the seal face 4106 in the range of about 5degrees to about 85 degrees, in some configurations about 10 degrees toabout 60 degrees, and in other configurations about 20 degrees to about45 degrees. The seal face 4106 or the seal member 4100 may comprise anyof a variety of elastic or flexible materials, including any of avariety of silicones such as NuSil Med-4035, Med-4820, and MED50-5338,may have a durometer in the range of about 20 to about 80, in someexamples about 15 to about 60, and in other examples about 20 to about40. The thickness 4110 of the seal face 4106 may be in the range ofabout 0.01″ to about 0.1″, in some examples about 0.02″ to about 0.05″,and in other examples about 0.025″ to about 0.03″. As illustrated inFIG. 15B, the seal face 4106 may be raised or offset from the body 4112of the sealing member 4100. The raised distance 4114 of raised seal face4106 may be in the range of about 0.01″ to about 0.2″, in someconfigurations about 0.02″ to about 0.1″ and in other configurationsabout 0.04″ to about 0.06″.

The body 4112 may comprise a lumen 4116 in communication with thesealing opening 4102. The lumen 4116 may have a uniform or non-uniformdiameter, cross-sectional area and/or cross-sectional shape. Lumens withnon-uniform diameters may taper toward or away from the seal opening4102, and the taper may be linear or non-linear. In some examples, thelumen 4116 may have an average diameter 4118 in the range of about 0.05″to about 0.5″ or more, in some configurations about 0.1″ to about 0.3″,and in other configurations about 0.15″ to about 0.2″. The lumen 4116may have a length 4120 anywhere in the range of about 0.1″ to about 1″or more, in some configuration about 0.2″ to about 0.5″, and in otherconfigurations about 0.25″ to about 0.4″. The body 4112 may have any ofa variety of shapes, including cylindrical, frustoconical, box-like orother shapes, and may be coupled to the guide tunnel by a frame orhousing.

As illustrated in FIGS. 13A to 13E, in one embodiment, guide catheter112 is used to access the subvalvular region 116 for delivery of acinchable implant. After passing a guidewire 118 through guide catheter112 and along subvalvular region 116, a multi-window tunnel catheter 120is passed down guidewire 118. In one embodiment, tunnel catheter 120 areleasable multi-window tunnel catheter as described in one or moreembodiments of U.S. Pat. Appl. Ser. No. 61/026,697, entitled“MULTI-WINDOW GUIDE TUNNEL” filed on Feb. 6, 2008, which is hereinincorporated by reference in its entirety. After guidewire 118 isremoved from tunnel catheter 120, a delivery catheter (not shown)carrying one or more deployable anchors 122 coupled to a tether issecured to the subvalvular region 116. Embodiments of various devicesusable with embodiments of the invention are described in U.S. patentapplication Ser. Nos. 10/656,797, 10/741,130, 10/792,681, 10/900,980,10/901,555, 11/201,949, 11/202,474, 11/232,190, 11/255,400, 11/270,034and 11/583,627, which are incorporated by reference in their entirety.

In other embodiments, any of a variety of catheters and intralumenalinstruments may be configured with one or more deformation zones. Inaddition to performing cinching of the subvalvular region about themitral valve, these catheters and instruments may be used for othertherapeutic and diagnostic procedures, including but not limited toaccess other cardiac valves(e.g. tricuspid valve, pulmonary valve andaortic valve), access to the coronary vasculatures, including thecoronary arteries and coronary venous vasculature, including thecoronary sinus, trans septal, transapical and other transmyocardialprocedures, electrophysiological procedures, implantation of cardiacrhythm management devices, genitourinary procedures, gastrointestinalprocedures including access to the hepatobiliary tree, cerebrovascularprocedures including implantation of vascular coils, and others.

While this invention has been particularly shown and described withreferences to embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the scope of the invention. For all ofthe embodiments described above, the steps of the methods need not beperformed sequentially.

1-15. (canceled)
 16. A method for treating a patient, comprising:providing a catheter having a lower durometer region comprising at leastone compressible portion and a greater durometer region comprising atleast two constricting portions in an alternating configuration with thelast least one compressible portion; bending the catheter such that theat least two constricting portions of the higher durometer regioncompresses the at least one compressible portion of the lower durometerregion; and passing a tubular body down a passageway of the catheter.17. A system for treating a patient, comprising: a guide cathetercomprising a longitudinal axis, a guide lumen, and at least onedeformation zone, the at least one deformation zone comprising twosegments of polymeric material of different durometers and alongitudinal interface therebetween with respect to the longitudinalaxis of the guide catheter; a tunnel catheter comprising a tubular bodywith a tunnel lumen, wherein the tubular body is configured forinsertion into the guide lumen of the guide catheter; and a deliverycatheter comprising an anchor retaining cavity and an anchor deliverymechanism, wherein the delivery catheter is configured for insertioninto the tunnel lumen of the tunnel catheter.
 18. The system of claim17, wherein the tubular body of the tunnel catheter further comprises aplurality of delivery apertures in communication with the tunnel lumen.19. The system of claim 17, wherein the longitudinal configurationbetween the two segments of polymeric material comprises a reciprocatinglongitudinal configuration.
 20. A method for accessing a cardiac regionof a patient, comprising: providing a steerable guide cathetercomprising two polymeric materials forming a longitudinal interfacetherebetween, where the two polymeric materials comprise a firstpolymeric material having a first durometer and a second polymericmaterial having second durometer greater than the first durometer;passing the steerable guide catheter through a cardiac valve orifice;compressing the first polymeric material with the second polymericmaterial about the longitudinal interface; and steering the steerableguide catheter into a subvalvular region adjacent the cardiac valveorifice.